Angiopteris evecta
Angiopteris evecta (G. Forster) Hoffmann, Mule's Foot Fern, has the distinction of being the only naturalized fern for which we have precise introduction information. It was brought to Hawai'i in 1927 by H. L. Lyon and planted in upper Mnoa Valley, O'ahu, in what is now the Lyon Arboretum of the University of Hawai'i. This fern has huge leaves that can reach more than 7 m in length and shade out large areas. Its spread within the Lyon Arboretum and into the nearby forested ridges and valleys was described by E. Funk (1987), who anticipated its continued spread (Funk 1987) . It became a pest in the arboretum and poses a similar threat in other areas where it grows. The plant that Funk reported as having been seen along the Hana Highway, East Maui, was no longer in evidence in 1994 and may have been destroyed (R. Hobdy pers. comm.). In 1994 Art Medeiros found A. evecta spreading into the lowland wet 
forest above Hana, Maui, where it probably escaped from cultivation in the tropical nursery Helani Gardens (R. Hobdy pers. comm.). It is now sparsely naturalized on Maui from Ke'anae to Hana (Medeiros pers. com.). In 1992 Angiopteris was collected on Hawai'i growing in the Waiakea Forest Reserve (Imoto & Bergfeld 03/31/92, HVNP). Several large plants are in cultivation on the Hamakua Coast, Hawai'i, on the grounds of the Hawai'i Tropical Botanical Garden. This wet coastal area seems particularly favorable for serving as a springboard for the naturalization of many alien plants, and the escape of Angiopteris evecta should be anticipated and guarded against.
